Japanese Patent Publication No. H6-10996 (hereinafter referred to as “Patent Literature 1”) discloses a locking connector that includes a housing having multiple conductive contacts, a cover, and two latch arms, which are plate springs made of a resilient metal. The latch arms are cantilever plates attached on opposite side surfaces of the cover. One ends of the latch arms are fixed to the opposite side surfaces of the cover, respectively; and hooks are formed at the other ends of the latch arm, respectively. The connector is designed to be mated to a pin header having multiple conductive pins. When the connector is mated to the pin header, the hooks of the latch arms are latched to the frame of the pin header.
In the configuration disclosed in Patent Literature 1, the latch arms resiliently deform and incline during mating of the connector to the pin header. When the connector completely mates to the pin header, the resilience of the latch arms restore the latch arms to their original shapes, whereby the hooks are latched to the frame of the pin header (see FIG. 4 of Patent Literature 1). When the latch arms in this state are pushed toward the side surface of the cover, the latch arms resiliently deform and incline, whereby the hooks of the latch arms are removed from the frame of the pin header.
It should be noted here that it is difficult to reduce the size of the conventional locking connector without significant degradation of latching reliability.
The permissible length of the latch arm increases as the length of the connector along its side in the direction from the base end to the fore-end (hereinafter referred to the “direction from the base end toward the fore-end”) increases. The longer the latch arms are, the less inclined angles of the latch arms during the latching and unlatching are; the longer the latch arms are, the higher the flexibility of the latch arms is. The smaller the inclined angles of the latch arms are, the smaller the displacement of the hooks in the direction from the base end toward the fore-end is. The higher the flexibility of the latch arms is, the more easily the hooks can be aligned with the frame of the pin header. Therefore, the longer the latch arms are, the more easily the latch arm can be latched and unlatched.
On the other hand, the permissible length of the latch arm decreases as the length of the connector along the direction from the base end toward the fore-end decreases. The shorter the latch arms are, the greater inclined angles of the latch arms needed for the latching and unlatching are; the shorter the latch arms are, the lower the flexibility of the latch arm is. The greater the inclined angles of the latch arms are, the greater the displacement of the hooks in the direction from the base end toward the fore-end is. The lower the flexibility of the latch arms is, the more difficult the alignments of the hooks with respect to the frame of the pin header are. Therefore, the shorter the latch arms are, the more difficult it is for the latch arm to be latched and unlatched. In other words, the shorter the length of the connector along the direction from the base end toward the fore-end, the more difficult it is to be latched and unlatched.
Not only the locking connector disclosed in Patent Literature 1 has the problem described above. The problem is common to locking connectors in general that have a cover and arm parts that are cantilever plate springs attached on the side surfaces of the cover and in which latching parts provided in the arm parts are latched to portions of a counterpart connector.